Sam's build thread

[sambb]

Happened across this youtube vid of what Malcom Oastler is up to. I know his OMS hillclimber is an E85 turbo Hayabusa. This says Ninjamobile so maybe he's building another weapon or its for someone else. I was proud when I did caster calcs on the car - look what he 'knocks up' in his spare time!:

YouTube

[Sydneykid]

FWIW 330 ft lbs is 447 nm, I'm not sure that I would be worried only about the engine at that level, the rest of the drive train may be the larger issue. To get that sort of torque efficiently means a lot of airflow, over 45 lbs per minute, that's a big turbo, not very circuit friendly.

Maybe I'm reading the Maxspeeding web site incorrectly but my understanding is that the pricing is in USD, then add freight plus GST.


Cheers
Gary

[sambb]

Gary check them out on Ebay. That's what I thought re the dollars on their website but definitely Aus dollars 260 bucks on ebay! The only thing I'm baulking at now is their lack of forced pin oiling. Most 1.8T 20V rods seem to rifle drilling but I still dont get the logic. Isn't that what squirters are for (including colling) and I'm pretty sure stock rods dont have it. The squirters aren't pressure regulated are they. They squirt continuously at all rpm yeah?

[Sydneykid]

Gary check them out on Ebay. That's what I thought re the dollars on their website but definitely Aus dollars 260 bucks on ebay! The only thing I'm baulking at now is their lack of forced pin oiling. Most 1.8T 20V rods seem to rifle drilling but I still dont get the logic. Isn't that what squirters are for (including colling) and I'm pretty sure stock rods dont have it. The squirters aren't pressure regulated are they. They squirt continuously at all rpm yeah?

I'm not an engine builder but I've never used a race con rod with forced pin oiling. There's plenty of oil for both lubrication and cooling trapped under the piston crown, which gets swapped on every change of piston direction. Even block mounted oil squirters had their run for a while but many have reverted to the oil feed slots in the side of the big end bearing when extra cooling is required.

Example;


These are the Argo I Beam rods like I used in my Skyline RB30/26 engine (rated for over 200 bhp each), note the little end oil hole for lubrication. I installed oil squirters in the RB30 block (bitch of a job) but I wouldn't bother now, I'd just slot the conrod big ends.



When I have a question about conrods I still revert to Fred Carrillo (https://www.cp-carrillo.com/p-30878-rods.html), "Force Feed Oiling, or Forced Pin Oiling (FPO), in actuality does not offer forced or pressurized oiling. However, by installing a slot behind the bearing and a hole through the center of the rod we have established a reservoir that supplies oil underneath the wrist pin when the connecting rod is pulling mass down the cylinder. It certainly contributes to the longevity, however it is only effectual on one of the four strokes of the engine cycle".

To answer your question directly, personally I wouldn't let the lack of forced pin oiling put me off any conrod.

Cheers
Gary

[sambb]

"Oil Reservoir on PE A larger "funnel" at the top oil hole gives a better chance to collect oil for the PE lubrication. It is often combined with a PE bump out. "


Looks like Carrillo (alternatively to FPI) do this to the pin end top hole - just sort of radius it to help it catch oil and guide it onto the pin I guess when the piston is moving up.

My confusion over the whole FPI thing is that it seems to be touted as being able to increase pin end longevity in street driven cars. That's what seemed to imply to me that the oil squirters were somehow deficient at low rpm. I always thought the size of their orifice would be designed that no matter what the oil pressure was doing, there'd be ample squirting up into piston/pin area. Maybe that's not the case with my engine but I cant seem to find any explanation why.

[sambb]

So after changing the orientation of my adjustable strut tops the other day I thought I'd first check to see that the castors were at least symetrical. Essentially you establish a straight ahead reference line ahead of the tyre on the ground. To do this at the straight ahead I used my toe plates with long rulers attached to work out this position. Then from this straight ahead reference line I put two divergent lines at 20 degrees from it both left and right. The camber gauge/jig I have was used and the idea is that you reference it to the ground plane and then fix to the wheel upright (which at that moment gives you your camber setting). You then turn the wheel to the inside 20 degree line and take a camber reading and then back to the outside 20 degree line and log that number too. The numbers are then plugged into a caster formula which gives you your caster. In practice its harder and more labour intensive than that. I could only line up the wheels accurately with the 20 degree lines with my toe plates, which meant that the camber jig had to removed each time. When I first fixed it on at the wheel straight ahead I put mark on the wheels for exactly where the jig should go back on after the toe plates had established the correct wheel angle.
So that's one of my questions. I was using the jig with the horizontal base plate so that the jig could be fixed to the wheel (theoretically) throughout the caster sweep. That's correct isn't it, that the jig should stay in the same spot on the wheel throughout the rotation?

My caster numbers came out as even on both sides but what concerns me is that their behaviour wasn't symmetrical left to right. For example on the passengers side the camber would eg -3.4 degrees camber when turning in and say +1.0 degree when turning out. But the drivers side would be -3.9 degrees when turned in but only +0.25 degrees camber when turned outward. The numbers even out when run through the equation yet the 'bias' on one side compared to the other is that the cambers are behaving a little differently. I even faced the car in the opposite direction on the ground and redid the whole thing to average out any defect in the measurements but the same thing could be seen on the same side.
My static neg cambers were -2.3 degrees even on both sides so I don't think it was mismatched camber doing it. Ride heights were equal too. 4mm toe out total. So I've probably buggered things up somewhere but for now on the street its close enough.

What was the most interesting thing to see was how 2.3 degrees neg camber could go to 3.5- 4 degrees neg with only a 20 degree wheel angle change. I can totally see now how you can get away with less camber provided there is plenty of pos. caster. On the road the car is significantly more pointy when mid corner. Until I get used to it I find myself at the apex with too much steering lock on and actually having to unwind the wheel as I'm getting too close to the apex. If toe out at the rear gets it turned in, lots of pos caster gets it through the mid corner nicely , then I cant wait to get the Kaaz LSD box fitted and see what that does to corner exit!!

My caster numbers came out at +6.4 degrees each side across a 20-20 degree (40 total) sweep. I remember Gary you saying that the actual caster number depends greatly upon the way its measured/sweep size etc so at the moment I'm not too fussed about the numbers (I know it has more than it had that's for sure) but just happy they appear to be equalish.
The slight loss of neg camber (.3 degree) from where I had it was to be expected and I'm sure I'll be able to recover that either from the ball joints adjustment or in the subframes.

So yeah I'll have to redo it all (perhaps the calibration of the gauge was funny but also I think calculating and arriving at those 20 degree lines on the ground has its inaccuracies) but it was a good little exercise to learn for now.

[Sydneykid]

A good lesson learnt, caster is the best thing ever, "camber on demand", it's why on average European cars handle better than most others, they have more caster.

I just count the steering wheel turns for the + & - 20 degrees, then I don't have to mark the floor anymore. If I am being pedantic I use the spirit level on the phone to get the steering wheel spokes at the same (repeatable) angle.

When measuring caster there is Ackerman effect, toe out increases with steering lock, as a result -20 degrees on the outside wheel will be more than +20 degrees on the inside wheel.

SAI can also effect caster readings, road cars often have slightly offset (left to right) SAI/Caster to help prevent the drift to the left, caused by the camber on the road so the water drains to the gutters.

Cheers
Gary

[Sydneykid]

"Oil Reservoir on PE A larger "funnel" at the top oil hole gives a better chance to collect oil for the PE lubrication. It is often combined with a PE bump out. "


Looks like Carrillo (alternatively to FPI) do this to the pin end top hole - just sort of radius it to help it catch oil and guide it onto the pin I guess when the piston is moving up.

Be careful, Carrilo rods only have the flare on the gudgeon pin oil feed when they have the strengthening bump (extra material) on the top of the rod under the piston crown.

My confusion over the whole FPI thing is that it seems to be touted as being able to increase pin end longevity in street driven cars. That's what seemed to imply to me that the oil squirters were somehow deficient at low rpm. I always thought the size of their orifice would be designed that no matter what the oil pressure was doing, there'd be ample squirting up into piston/pin area. Maybe that's not the case with my engine but I cant seem to find any explanation why.

The oil squirters are oil pump fed, obviously the oil pump pumps more as the engine rpm increases. It's the same for all oil lubricated bearings in the engine. Lower rpm also means lower inertia which is what pushes the oil up the FPO. So the oil flow via FPO is going to be less at lower pm too.

I'd be surprised if the oil flow is ever too low to the gudgeon but a small slot/s in the conrod, aimed at the underneath of the piston crown (refer ZRP rod above), would solve it without the risk associated with FPO.

Cheers
Gary

[Sydneykid]

It may be also worthwhile having a look at how VW limit the oil flow to the squirters, it could be something as simple as them individually having only a small oil feed hole or it could be a restrictor inserted in their oil feed gallery. Either way you could increase the hole sizes a tiny amount so that they flow a bit more at low rpm.

Cheers
Gary

[sambb]

So Gary do you think the fact that one side at 20 degrees out had a touch more camber than the other wheel at the same angle is likely just that I wasn't able to transfer the 20 degree lines exactly onto the ground (or line the wheels accurately with them)? That's what I'm hoping. Because at the end of the day the formulas pumped out the same final caster numbers for both sides.

Yep I've done a bit of oil squirter research and yes it does turn out that the squirters vary. Some are longer and the orifice is smaller ( I assume that would limit peak flow but squirt stronger at low rpm) and others are a much bigger. I think the safest thing to do would be to find out what BAM 1.8T 20V squirters look like since i'll be running that wrist pin size with that piston.